IGDA Game Design SIG
The IGDA just launched a new Game Design Special Interest Group (SIG), which I joined right away. It focuses on the actual design aspect of games, as opposed to programming, art, writing, and so on.
The SIG welcomes people working or studying both video games and tabletop games. It’s young and still finding its footing, of course, but if you fall under its remit, consider contacting the Google group‘s owner Sande Chen for admission to the group.